The Queen has given her name to a new honour to recognise the loss suffered by the families of armed forces personnel killed on operations, the Ministry of Defence announced today.

The Elizabeth Cross, a hallmarked silver brooch with a smaller pin-on version, and an accompanying memorial scroll, will be given to the next of kin of those who died on operations, including UN peacekeeping, for which participants currently get campaign medals; those killed by terrorism; those who died on other operations where death was caused by "the inherent high risk of the task"; and those who died later as a result of injuries in those cases.

The award will be retrospective covering deaths since the second world war. Up to 8,000 people could receive the honour, defence officials said.

Asked what categories might be covered, Air Chief Marshal Sir Jock Stirrup, chief of the defence staff, said: "There are always very difficult issues around the boundary. Each will be addressed on its merits." He emphasised that the honour was not a medal but "an emblem".

In a message on the British Forces Broadcasting Service, the Queen said: "This seems to me a right and proper way of showing our enduring debt to those who are killed while actively protecting what is most dear to us all."

The Elizabeth Cross will carry the rose of England, the Scottish thistle, the Irish shamrock, and the Welsh daffodil. The memorial scroll will carry the royal coat of arms and the Queen's signature. It will carry the words – chosen on the advice of previous poet laureate Andrew Motion – "This scroll commemorates … who gave his/her life for Queen and country."